1,155 research outputs found
Respuesta a los comentarios de Francisco Gómez Camacho
No full textReply of Aldo Figueroa, author of “Income Distribution In Peru”, Lima, Instituto de Estudios Peruanos, 1975, to the comments of Francisco Gómez Camacho about the book.Respuesta de Aldo Figueroa, autor del libro "Distribución del Ingreso en el Perú" (Lima, Instituto de Estudios Peruanos, 1975) a los comentarios de Francisco Gómez Camacho sobre el libro
Reply to the comments of Francisco Gómez Camacho
No full textRespuesta de Aldo Figueroa, autor del libro “Distribución del Ingreso en el Perú“ (Lima, Instituto de Estudios Peruanos, 1975) a los comentarios de Francisco Gómez Camacho sobre el libro.Reply of Aldo Figueroa, author of “Income Distribution In Peru”, Lima, Instituto de Estudios Peruanos, 1975, to the comments of Francisco Gómez Camacho about the book
Respuesta a los comentarios de Francisco Gómez Camacho
No full textRespuesta de Aldo Figueroa, autor del libro "Distribución del Ingreso en el Perú" (Lima, Instituto de Estudios Peruanos, 1975) a los comentarios de Francisco Gómez Camacho sobre el libro.Reply of Aldo Figueroa, author of “Income Distribution In Peru”, Lima, Instituto de Estudios Peruanos, 1975, to the comments of Francisco Gómez Camacho about the book
Cosas de los Estados Unidos
No full textThe author Simón Camacho wrote the book under the pseudonym Nazareno. Edited by James Durand. It contains letters and sketches covering the years 1856 to 1863. Includes the author\u27s portrait, engraved by J.A. O\u27Neill from a photograph by Fredericks. Also contains a reproduction of the author\u27s signature. Spine title: Cosas de los E. Unidos.https://stars.library.ucf.edu/civilwar-text/1006/thumbnail.jp
Synthesis of MoC@Graphite NPs by short and ultra-short pulses laser ablation in toluene under N2 atmosphere
No full textARTICULO CIENTÍFICOIn this work, we present the experimental methods of the synthesis of MoC/MoC@Graphite by laser ablation
with short and ultra-short laser pulses by using a molybdenum (Mo) and graphite target. All the experiments
were carried out utilizing toluene as liquid medium. During the ablation, a nitrogen (N2) atmosphere was necessary to avoid the oxidation of the Mo NPs. The structure, composition, and morphology of the NPs were
investigated by transmission electron microscopy (TEM-HRTEM-SAED), X-ray diffraction and Raman spectroscopy. The TEM results evidence the formation of two carbonaceous structures: a graphite coating around the
NPs and an amorphous carbon matrix that embeds the NPs. It was observed that these structures contribute to
avoid the agglomeration and oxidation of the NPs. The size distribution, structure, and agglomeration of the NPs
were discussed based on the solvents and also on the duration of the laser pulses.This work was supported by CONACYT (Grant No. 280518) and
UAEM (Grant Number 1025/2014RIFC). We also thank Dr. Uvaldo
Hernández from CCIQS for technical assistance in DRX. The author
Madrigal-Camacho thanks to CONACYT for the Grant No. 708628
Estudio de Coherencia y Transporte Cuánticos en las Dinámicas Energéticas duranta la Captación de Energía Lumínica en Sistemas Fotosintéticos
No full textThe photosynthesis is one of the most studied biological processes through history. Its capacity to fix carbon into nutritional molecules is the base of all food chains. Its efficient exploitation of the solar energy inspires application such as solar cells, or synthesis of biologically important compounds.
During the first miliseconds of the photosynthesis, sunlight is harvested and transfered to a reaction center, were it powers the conversion of carbon dioxide into carbohydrates and other fuel molecules. The understanding of the dynamics in this process is essential for the design of similar systems.
In the last decades, ultrafast multidimensional electronic spectroscopy techniques have revealed the presence of quantum phenomena, such as quantum coherence and transport, during the energy transport in the photosynthesis, which are suggested to contribute to its unusually large efficiency.
Although the presence of quantum phenomena in photosynthetic complexes can be probed empirically, its application is limited by the technique difficulty, highly expensive equipment, complex data analysis and its low transferability to in vivo samples. As such, in silico techniques provide a platform to study these phenomena without this experimental limitations.
In this work, the study of the presence of quantum coherence and quantum transport in a protein-pigment complex is presented through fully computational methods. First, a methodology is developed and validated for the calculation of highly accurate spectroscopical parameters of the complex. From these, quantum master equations are used to obtain the dynamics of the excitation energy transport, and probe for the quantum effects and its prevalence, in order to elucidate mechanisms and factors that may extend their lifetime.La fotosíntesis es uno de los procesos biológicos más ampliamente estudiados en la historia. Su capacidad para fijar carbono en moléculas nutritivas es la base de toda cadena trófica, y su eficiente explotación de la energía solar inspira aplicaciones como las celdas solares o la síntesis de compuestos de importancia biológica.
Durante los primeros milisegundos de la fotosíntesis, la luz solar se absorbe y transfiere a un centro de reacción, donde provee de energía a la conversión de dióxido de carbono en carbohidratos y otras moléculas combustibles. La comprensión de las dinámicas energéticas en este procesos es esencial para el diseño de sistemas similares. En las últimas décadas, técnicas de espectroscopía electrónica ultrarápida y multidimensional han revelado la presencia de fenómenos cuánticos, como el transporte y la
coherencia cuántica, durante el transporte de energía en la fotosíntesis; estos se sugieren que
contribuyen a su eficiencia inusualmente alta.
A pesar de que la presencia de fenómenos en complejos fotosintéticos puede ser investigada empíricamente, su aplicación es limitada debido a la dificultad de la técnica, alto precio de los equipos, análisis de datos complejo y poca aplicabilidad en muestras in vivo. En consecuencia, las técnicas in silico proveen una plataforma para el estudio de estos fenómeno sin estas limitaciones experimentales.
En este trabajo, se presenta el estudio de la presencia de coherencia y transporte cuánticos
en un complejo proteína-pigmento a través de métodos completamente computacionales. Primeramente, se desarrolla y valida una metodología para el cálculo de parámetros espectroscópicos con alta exactitud.
A partir de estos, se utilizan ecuaciones cuánticas maestras para obtener las dinámicas de transporte energético, para analizar fenómenos cuánticos y su prevalencia en aras de dilucidar mecanismos y factores que puedan extender su vida media.UCR::Vicerrectoría de Investigación::Sistema de Estudios de Posgrado::Ciencias Básicas::Maestría Académica en Químic
El Tlacuache Núm. 248 (2007). 248 Año 7 (2007) febrero. El Tlacuache
No full textEl Alcázar de Diego Colón por Juan Antonio Siller Camacho. - Con semillas, palitos y hojitas por Laura Parrilla Álvarez. - El Yauhtli por Margarita Avilés y Macrina Fuentes
El Tlacuache Núm. 486 (2011). 486 Año 11 (2011) septiembre. El Tlacuache
No full textLa incursión de los Franciscanos en el Valle de Tula por Carlos Alberto Reyes Vélez. -La Feria de Tlaltenango. -Medalla al mérito por Juan Antonio Siller Camacho. -Testimonios de una Guerra. Fotografía de la Revolución Mexicana
Anchieta fasciatella Ardila-Camacho & Calle-Tobón & Wolff & Stange 2018, new combination
No full textAnchieta fasciatella (Westwood, 1867), new combination Fig. 3a Mantispa (Trichoscelia) fasciatella Westwood, 1867: 503. Holotype (or syntypes), female, Venezuela (OUM). Specimens examined. New records: Panama: Canal Zone, Albrook Forest Site, 30.40 m, 25‒26.VII.1968, black light trap, R. S. Hutton, (1 ♂ — UAAM); same but 13‒14.VII.1967, Hutton & Llaurudo, (1 ♂—UAAM); same but 24‒25.VIII.1967, black light trap, Hutton & Llaurudo (2 ♂‒UAAM); same but 29.II‒1.III ‒1 968, R.S. Hutton, (1 ♂—UAAM); same but 3‒4.VIII.1967, Hutton & Llaurudo, (2 ♂—UAAM); Darién, Punta Patiño, 7.VIII.1952, F. Blanton (1 ♂ — FSCA); Panamá, 7-10 km. north El Llano, 14‒22.V.1993, E. Giesberg (5 ♂ — FSCA); Panamá Oeste, Barro Colorado Island, 18.IV.1874, Duckworth (1 ♂ — USNM). Distribution. Colombia (Bolívar, Magdalena, Santander; Ardila-Camacho & García 2015), Panama (Canal Zone, Panamá Oeste, Panamá, Darién). Comments. The genus Anchieta is until now composed of seven species distributed from Panama south to Brazil. Most of the species are known from the Brazilian Amazonia, although the genus presents few records (Penny 1982). The group is separated from other Symphrasinae members by the presence of a straight rarp2 (second anterior radial cell) of forewing. Another remarkable difference, is the mimetic pattern with several families of Hymenoptera, which seems to be a generalized feature of the group. For example, A. fumosella was referred to be a mimetic of Vespidae (Buys 2008), while A. fasciatella resembles wasps of the family Braconidae (Braconinae), which have repugnant abdominal glands (Ardila-Camacho & García 2015). The remainder species present a general color pattern and the hindtibia greatly swollen and flattened, resembling stingless bees of the tribe Meliponini (Penny 1982). Some species in this genus have lateral keel like projections on the abdominal tergites of both sexes. The pterostigma on the forewing is shorter than in Plega or Trichoscelia, and the trochanter of the forelegs has a dentiform process on the inner surface. Anchieta fasciatella was originally described from Venezuela. However, this record is now considered erroneous because the type locality, Santa Marta, is not located in Venezuela, but in Colombia. In fact, Ardila- Camacho & García (2015) reported this species as Plega fasciatella from several localities in Colombia. Moreover, in the revision by Penny (1982), this species was mentioned as occurring in Panama, however, no specific data were provided by the author. Here we present the first specific records of this species from Panama.Published as part of Ardila-Camacho, Adrian, Calle-Tobón, Arley, Wolff, Marta & Stange, Lionel A., 2018, New species and new distributional records of Neotropical Mantispidae (Insecta: Neuroptera), pp. 295-324 in Zootaxa 4413 (2) on pages 297-298, DOI: 10.11646/zootaxa.4413.2.4, http://zenodo.org/record/122696
Morphological abnormalities in a population of Pleurodeles waltl (Caudata: Salamandridae) from southwestern Spain
No full textPrevalence of morphological abnormalities usually is less than 5% in most amphibian populations (Ouellet et al. 1997, Vandenlangenberg et al. 2003, Mester et al. 2015). Morphology is closely related to whole-organism performance in amphibians (Zamora-Camacho 2018, Zamora-
Camacho and Aragón 2019a), and thus, is under strong selection (Watkins 1996). Therefore, this low frequency likely reflects the negative effects of abnormalities on whole-organism performance (Zamora-Camacho and Aragón 2019b). However, amphibian populations are experiencing an
alarming increase in morphological abnormality rates worldwide (Lanoo 2008, Johnson and Bowerman 2010, Laurentino et al. 2016). Amongst these, the most common are limb malformations, such as misshapen or fused limbs, and missing, or presence of extra limbs and toes (Harris et al. 2008, Johnson and Bowerman 2010, Reeves et al. 2013).The author was partially supported by a Juan de la Cierva-Formación postdoctoral fellowship from the Spanish Ministerio de Economía, Industria y Competitividad
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